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The Mystery of Flight 587
Brother Jonathan Gazette -- Scroll Down all the way ^ | 11/15/2001 | Marshall Smith

Posted on 11/24/2001 5:35:14 PM PST by Swordmaker

(Brother Jonathan News, November 15, 2001) On Monday, November 12, 2001 American Airlines Airbus A300 Flight 587 crashed and burned, just two minutes and 24 seconds after take off from JFK International Airport in New York City. Within minutes the speculation for the cause ran from aircraft failure to terrorist attack. Immediately, both the FBI and the NTSB began a formal investigation. The NTSB was in charge of investigating the crash and the FBI would take over if evidence of sabotage were found. So far, the investigators have eliminated a number of possible theories, such as birds damaging the engines, simple engine failure, or possible bomb or missile attacks.

On Tuesday, the 13th, during the NTSB press conference, one of the reporters asked, "What about the possibility of a thrust reverser failure?" The reporters were told there was no evidence of that and its not possible for that to occur during flight. What the NTSB and FBI failed to tell the reporters is that it is not possible for there to be a thrust reverser failure in flight, UNLESS the thrust reverser controls were sabotaged by a terrorist. Instead, the investigation seems to focus on the possibility that wake turbulence from a 747 jumbo jet which had taken off just minutes before Flight 587 had caused the damage to the plane and caused the crash.

What is confusing to most knowledgeable aircraft investigators is that this is completely impossible. It is not possible for any type of turbulence to rip off the tail of an airplane, and then have it go out of control in such a way that both engines would also fall off. In August 1985 a Japanese Boeing 747 with the vertical tail assembly completely torn away continued to fly in large circles for over half an hour before it hit a mountain. But only because the pilots were busy trying to figure out what happened to the plane and did not watch where they were going. It did not go into an instant out of control spin with complete loss of the engines.The Air Force's B-2 Flying Wing stealth bomber is a perfect example to prove that a plane with absolutely NO vertical fin or stabilizer is able to fly and does not instantly become unstable and crash. The B-2 uses modern "fly-by-wire" computers to keep the plane flying straight and level. The original flying wing design from the 1950's also flew but using manual flight controls made it rather difficult to steer with no rudder. The Airbus A300 uses a modern "fly-by-wire" computer system and would fly quite easily with complete loss of the vertical fin and rudder. The NTSB's claim that the loss of Flight 587's vertical fin and rudder might be the cause of the loss of the control of the plane which caused it to crash is both misleading and deceptive.

Any theory blaming the failure of the vertical fin and rudder assembly as the cause cannot account for why the engines would fall off the plane. Any theory blaming an engine failure as the cause cannot account for why the tail assembly would snap off cleanly with no appearance of blast damage from an exploding engine. Thus there would need to be three separate simultaneous failures, of the tail assembly and both pylons holding the engines on the plane to account for those three effects observed before the plane crashed. Most air accident investigators would easily conclude that the chances of three simultaneous airframe failures all occurring at the same time is not probable. It must be one or the other but not all three. It would be much easier to conclude that something else actually caused all three failures. Thus the breaking off of the tail and both engines is not the cause of the crash, but is the effect of some other single failure which caused the crash. And what would that be?If the left engine thrust reverser had either partially or completely actuated during flight, it would cause the plane to go into a flat spin to the left. The airplane would spin something like a flat Frisbee with the right engine pushing forward and the left engine pushing backwards. Within a second of the flat spin occurring, the sideways wind blast would rip off the tail assembly since it was never designed to take such a side blast of air.

As soon as the tail assembly broke off there is now very little wind resistance to the flat spin. At this point the engines would cause the aircraft to spin even faster with the g-forces away from the center of the spin becoming so great that both engines would be violently ripped off the wings and thrown outward away from the plane. This accounts for why the engines were found so far away from the crash site and why the tail came off first. Thus a single point failure, the in-flight actuation of the left engine thrust reverser, can account for all three observed phenomena of the clean breaking off of the tail and the failure of both engine pylons holding the engines. But how can that happen when there are so many safety devices to ensure that it never occurs?

That is quite simple. The American Airlines Airbus was parked overnight in preparation for its flight to Santo Domingo the next morning. During the night, a terrorist saboteur disguised as a ground crew mechanic could reach up in the back of the left jet engine and with a pair of diagonal cutter pliers simply cut the hydraulic line going to the thrust reverser actuator and the control safety sensor lines. The next morning about an hour after the jet engines were started, the hydraulic fluid now under pressure would drip from the cut line until none was left in the line and the thrust reverser would simply slowly drift into the full on condition while in flight and a catastrophic crash would occur only seconds later.

Until September 11th, 2001, nobody would have believed that 19 airplane hijackers armed only with box cutters could bring down both towers of the World Trade Center. But now we know better. Is it now so hard to believe that a single terrorist armed with a pair of pliers could bring down an A300 Airbus? This is called "asymmetric warfare," or "thinking outside the box," or simply using low-tech tools in a new way to destroy the high-technology of an advanced culture.Is it possible to show that the in-flight actuation of the left thrust reverser is the actual cause of the Flight 587 Crash? Yes. But you would probably ask, "How do you know such things?" First, I have been a pilot since 1962. I have put planes in almost every possible flight configuration. I am not a flight instructor, but for years I taught ground school classes in airframes, aircraft engines and air navigation. Second, I have degrees in mechanical and electrical engineering and physics, and for many years I was assigned to do failure analysis for many NASA Space Shuttle incidents.

In 1983, two communications satellites were left useless in low-orbit because the firing mechanism to launch them into hi-orbit failed. Several years later Shuttle flights recaptured the failed satellites and I was tasked to determine the cause of the failure. In three days of analysis I found the cause and the controls were redesigned and the failure never occurred again. In 1987, the Air Force was launching a secret satellite from the Shuttle using a Boeing supplied launch system. The actuators for the launch system were made by UTC. Final checks before launch showed that one of the actuators appeared to be faulty and had failed the initial tests at UTC but somehow had been installed into the Shuttle anyway. My task was to prove that the actuator was not faulty but only appeared faulty due to an improper testing device. In four days I found the faulty test device and proved the launch actuator was in fact ready for space flight. I did my usual scientific analysis "dog and pony show" for two Air Force Generals, and the Vice-presidents of both Boeing and UTC. Everybody was happy. The Air Force got their satellite on orbit on schedule. The VPs from Boeing and UTC were happy since they did not need to pay the $5 million penalty the government would assess for unstacking the Shuttle to replace the "defective" launch actuator and for delaying the project. Thus, what I am about to explain comes from many years of flight experience, along with years of experience in aerospace failure analysis.

According to the publicly available information from the NTSB, the Cockpit Voice Recorder (CVR) shows everything was normal in the flight until about 107 seconds after the initial run-up of the engines as Flight 587 began to roll down the runway for takeoff. At this point in time the plane is about 3,000 feet in the air and the sound of an "airframe rattle" is heard in the CVR record. No explanation was given for this noise. But as I propose, what was happening was the left thrust reverser was starting to close and this caused the plane to turn to the left. The pilot would compensate by using his feet to apply right rudder to bring the nose back to straight flight by turning to the right. When applying strong right rudder this usually causes the left wing to tilt upward so most pilots would instinctively also apply opposite or left aileron to keep the plane straight and level. Most pilots would recognize this flight configuration as a side-slip. This would be a rather strange maneuver for a commercial airliner especially during take off. This is often called the "poor mans air-brakes" since this odd configuration results in the opposite compensating controls surfaces to stick out in the wind and really slow down the aircraft.

I have done this maneuver many times in small aircraft to quickly lose airspeed or drop in altitude in preparation for landing. During this condition the burbling air flowing over the extended control surfaces makes a lot of noise and seems to make the plane shake, rattle and roll. This would account for the airframe rattle noise heard on the CVR at 107 seconds into the flight. The pilot probably thought he had overcompensated and was worried about losing too much airspeed and so then returned the controls back to normal and the rattling momentarily stopped. But the plane continued to turn back to the left. Seven seconds later, one of the flight crew comments about "air turbulence" with no further comment, and it would seem the pilot again tried to compensate for the strong drift of the plane to the left caused by the partially closing thrust reverser by again applying strong right rudder and opposite aileron as the same rattling sound is heard again several seconds later at 121 seconds into the flight. Four seconds later, at 125 seconds into the flight, the first officer calls for "full power" presumably to compensate for the side-slip maneuvers which had really slowed the plane down to dangerously slow speed. This was a fatal mistake, but not caused by the pilot.

As soon as the power went to full, the spinning effect caused by the partially or fully actuated thrust reverser would cause the plane to now spin out of control in a flat spin. Two seconds later, at 127 seconds, the CVR shows one of the flight crew makes a comment about being out of control. No more comments are made after that and the recording ends 17 seconds later when the plane hits the ground. But what happened when the captain called for full power?

If the pilot were holding full right rudder and almost full left aileron to compensate just as the left thrust reverser came into the full on position, the application of full power would have greatly increased the turn to the left and would have created a huge side force on the tail and rudder assembly which simply broke off cleanly and fluttered away. Within another second, without the vertical tail assembly to slow the spin, the plane would have begun to spin violently to the left about the center of gravity of the airplane. It now was not an airplane but a giant spinning Frisbee, or maybe a giant horizontal boomerang. Yes, you can take a scale model airplane and holding one wing throw it like a boomerang and make it fly. I know, since I used to do that as a kid. It works. A modern swept-wing jet aircraft with the tail torn off is simply a boomerang with a large stick, the passenger cabin, stuck in the middle.

Since the pilot had been holding opposite or left aileron, as soon as the plane started to spin, the left wing would be going backwards. But with the left aileron in the upward position the left wing becomes a lifting surface which keeps the spinning plane level, since both wings are lifting. The plane is now spinning horizontally with the full power from both engines increasing the spin faster and faster until both engines break off and are flung sideways away from the plane. As soon as the tail assembly broke away and the spin started, the plane became like one of those spinning centrifuges used by the astronauts for testing at high g-forces.

Within a second or so the people at the front and back of the plane were being thrown violently away from the center of the plane with a tremendous force. The seats with passengers in the very back of the plane were probably ripped out of the floor and thrown to the back of the plane. The flight crew at the front of the plane were thrown violently forward with such g-force they were instantly rendered unconscious or killed. This would explain why no more comments from the flight crew are heard after applying full power. The plane was spinning horizontally to the left completely out of control.

With the engines still running at full power, they broke away ripping the fuel tanks in both wings and Fight 587 became a flaming Frisbee. Something which nobody, and especially none of the people who witnessed the accident, had ever seen before. Small pieces of the airframe along with the engines were thrown by centrifugal force away from the flaming plane, giving the appearance of an explosion blasting parts away.

This also accounts for the many strange witness reports. I watched the news channels live and heard many witnesses swear that they saw the left engine come off first. Many other witnesses also were just as sure that the right engine was the first to come off. How to account for these strange opposite reports? Simply, all those witnesses had never seen a plane in a flat spin before. In a flat spin most of the plane's forward motion is stopped and the plane is like a spinning flaming Frisbee floating in the air. The flames hid the shape of the plane and the witnesses could not see the plane spinning, they only saw a ball of fire with pieces of plane blasting out from the center. At that point the concept of right or left engine no longer has any meaning, they are both going in the same circle. Thus depending on where the witness observer was standing when the first engine dropped off, half of the people would see it as going to the right and the other half would see it as going to the left. Thus both groups of observers were correct in reporting what they saw, they only misinterpreted what it meant.There were even professional pilots who reported they saw the plane in a "spinning nose dive." Is it possible that they were also mistaken? Is it possible the plane was not in a nose dive but was actually spinning flat with one wing going backwards, all caused by a thrust reverser actuated in flight? Since the other pilots reported they saw a flaming spinning plane arcing into the ground, and since they too probably had never seen a plane in a flat spin, they simply assumed what they saw was a spinning plane nosing into the ground. Is it possible to prove that it was not a plane nose-diving into the ground but a flat spin caused by a terrorist? Yes.

When the plane began the flat spin right after the tail assembly broke off over Jamaica Bay, the passengers in the front and back of the plane would experience high g-forces which threw them to the front and back of the plane. But those passengers in the center of the plane between the two engines and over the wings would simply spin around with no lateral g-forces. They would just spin around similar to sitting and spinning on a rotating piano stool. For them the plane simply floated downward as they rotated. What would happen to them? According to a statement made by New York mayor Giuliani in a news conference on Wednesday November 14th, the rescue workers recovered 262 bodies including "a man still holding a baby." How is that possible if the plane had nose-dived into the ground?

A nose dive into the ground would have produced such a violent forward force that all objects in the plane would have been thrown forward with most of the seats ripped out of the floor. Certainly no man can be strong enough to hold on to a baby through that force, unless instead the plane was in a flat spin. For the passengers in the center of the plane the force would have been downward as the plane hit the ground and the baby would be simply forced deeper into the man's lap as he sat in the passenger seat. Is that sufficient evidence to prove the plane was in a flat spin at impact with the earth and the crash was caused by a thrust reverser being actuated in flight? Yes. It could not have been a forward nose dive.

Further evidence is shown by the fact that on the many live news videos of the crash scene as the firemen are putting out the flames, a large section of the central portion of the plane is lying on the ground almost intact but in flames. If the flaming spinning Frisbee of Flight 587 had impacted the ground in a flat spin the front and back ends of the plane would have impacted with high rotating speed and thrown pieces of the plane, including the Flight Data Recorder in the rear of the plane many blocks away. But the center of the plane would be left intact. Analysis of the debris field would show material from the front of the plane went in one direction while material from the back of the plane went in the opposite direction. Is there clear evidence for sabotage by a terrorist? Yes. But it seems the FBI does not want to know. Maybe the airlines, especially American Airlines, do not want anybody to know they are so easily vulnerable to terrorist attack. For whatever reason, it seems the NTSB and the FBI do not want to know what happened to Flight 587. The clear evidence for the flat spinning impact is shown by the condition of the passengers and seats in the front and rear of the plane compared to the conditions in the almost intact center portion of the plane. Is the NTSB going to reassemble the plane parts to investigate that? According to NTSB Chairman Marion Blakey in the news conference on Tuesday the 13th, the NTSB was not going to reassemble the plane for analysis. The two engines are being sent under sealed bonded cover to American's Tulsa, Okla. facility for disassembly and analysis. But it would seem the engines were not the cause of the crash, so that is an investigative dead end. The real evidence, the conditions of the cabin and fuselage which would show and prove the plane crashed while in a flat spin, is simply going to be carted away and tossed in the trash. The FBI will never find the terrorist who caused the crash, if they are not looking for one.

----------- Marshall SmithEditor, BroJon Gazette

NEW FLIGHT DATA RECORDER UPDATE NOV. 17, 2001
The above article was prepared and written based only on data from the Cockpit Voice Recorder. The NTSB has since then released data from the Flight Data Recorder showing the position of controls and configuration of the aircraft. It is entirely consistent with the above analysis, including the turns to the left, right, left, right with the "rattling" occurring during the two turns to the right. Followed quickly by the loss of the vertical tail assembly, then the rapid break into a flat spin.
The FDR data shows: " ... the Airbus began a series of oscillations, yawing from left to right, then back again. Seconds later, the data stream from the Airbus's rudder 'becomes unreliable,' (meaning it had torn off) ... the jet began rolling to its left side ... the flight data recorder shows the Airbus rolled 25 degrees to the left, even though the pilots applied full-right roll control. The recorder also shows the jet dropped into a 30-degree dive, and began revolving rapidly toward the left.

Note, it does not say it "began rolling rapidly" to the left. It says it "began revolving rapidly" to the left. And that would be known as a flat spin. The rapid revolving was due to the engines at full power. Most pilots would recognize the 30-degree drop at the end as slowing to the stall speed as if the plane were simply stalling or entering into a recoverable vertical spin. A single engine plane would be very difficult to fly into a horizontal or flat spin. But any twin or mulit-engine plane like the A300 can easily enter a non-recoverable flat spin when reaching the stall point if the forward thrust on each side of the plane's centerline is not equal. The worst case being equal and opposite thrust around the plane's center of gravity caused by an inflight actuation of a thrust reverser.
The NTSB continues to insist there is no evidence of a terrorist attack. (The Brojon Gazette throws up its hands in complete disbelief.


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To: David
Concerning the "fly-by-wire" control system - I doubt that the Airbus A300 control system is as sophisticated as the active stability and control system used on the B-2 and other tailless aircraft. I think, but don't know 100% positively, that the control system is electronic - they use sensors to sense the rudder pressure, then wires give signals to the control surfaces (like, rudder - deflect 8 degrees) rather than the old system of pulleys and cables connected directly to the rudder pedals or the stick. On the tailless aircraft, the computer system senses the aircraft stability and modifies the control inputs to the control surfaces to stabilize the aircraft.

Anyone else know for sure?

41 posted on 11/24/2001 8:09:44 PM PST by RandyRep
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To: David
"Cicero, you are wrong. To the contrary, the Airbus is a pure fly by computer airplane."

The A-320 is. But this was an A-300, which is not "pure fly by computer".

42 posted on 11/24/2001 8:45:04 PM PST by okie01
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To: Swordmaker
I do not buy the thrust reverser theory as the redundancy of the thrust reverser systems means that multiple sabotage would have to take place. Two solenoid control valves, mechanical locks and the power drive actuators would have to be tampered with along with enunciators in the cockpit showing the thrust reverser had come out of lock. As previously stated, almost all domestic airlines had to retrofit their thrust reversers with multiple fail-safes which include mechanical locks. Per the article and comments, the thrust reversers were found stowed.

From witnesses on the ground indicate the aircraft was experiencing a compressor surge in one of the engines. The popping sound and flames are the trademarks. A compressor surge used to be common with older engine but rare by today's standards with the digital engine controls. The compressor surges, putting out the flame within the engine, the engine loads up with unburnt fuel and when the engine goes into automatic restart, it produces a loud bang and lots of flames. Most engines are made to withstand these backfires but last year; an Alaska 757 had a serious compressor surge that blew off the front cowl of the engine, damaging the engine and wing which forced an emergency landing. They can be quite violent. Witnesses stated that the engine made popping sound and flame could be seen between the wing and body. They also state that parts of the wing left the aircraft and hit the tail. The one report indicates that the flaps were fully retracted as indicated by the black box but have all the panels been accounted for on the ground? I am curious as to what else was they had dredged from the bay.

The flat spin does account for the break up of the aircraft and lost of vertical surfaces but the cause still seems to be engine failure with possible damage to flight surfaces. The full thrust of one engine without rudder control would put it into flat spin. The popping sounds heard would indicate that one engine was not working properly. Fuel delivery seemed to be intermittent or low. The rumblings may be key.

My theory is a main tire exploded after stowing (first rumble), causing damage to fuel feed line and pumps within the wheel well. This downed a 727 in Mexico in the 70s which caused the segregation and protection of hydraulics and fuel lines running within the wheel wells. This lesson has been lost on modern aircraft designers which routinely run hydraulics and fuel lines through the wheel wells without any shrapnel protection. The second rumble was the engine starting to miss from lack of fuel and going into a series of compressor surges that loosen something that hit the tail causing lost of rudder control (three violent full swings were recorded).

The crash and fire usually make analysis of wheel failure impossible to determine but I would start looking there.

43 posted on 11/24/2001 8:59:22 PM PST by Traction
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To: Swordmaker
Not a technical comment, but I wrote US News after reading their article on the crash in their Nov 26 issue strongly criticizing them ("shoddy reporting") for making no mention or explanation of the eyewitness reports of fire and explosion/disintegration, nor any mention of the MTA bridge surveillance tapes turned over to the FBI (why not the NTSB) which reportedly showed 587 taking off. Do the tapes show the aircraft flying apart less than three minutes into the flight? Inquiring minds want to know.
44 posted on 11/24/2001 9:03:16 PM PST by First Conservative
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To: Swordmaker
BUMP
45 posted on 11/24/2001 9:12:26 PM PST by Native American Female Vet
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To: Sabertooth
bump
46 posted on 11/24/2001 10:42:08 PM PST by RonDog
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To: Swordmaker
Bump.
47 posted on 11/24/2001 10:59:46 PM PST by patriciaruth
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To: First Conservative
Complicated, what?
48 posted on 11/24/2001 11:16:06 PM PST by tuesday afternoon
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To: RandyRep
Thanks for you comments. I posted this here for just this kind of feedback.
49 posted on 11/25/2001 12:06:11 AM PST by Swordmaker
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To: RandyRep
From here.

Within the high mud walls of this compound,members of Mr bin Laden's clan lived ...

There is a catalogue of electronic switches published by the Japan Aviation Electronics Industry and an empty box that once contained a kit for building a toy lorry.


An aviation switch catalog. Hmmm.
50 posted on 11/25/2001 12:37:40 AM PST by republius
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To: Chad
Hydraulics power all major aircraft systems including brakes and nose-wheel steering. I doubt Flight 587 would even have been able to taxi to the runway for takeoff had this "cut line" scenario occurred.

A friend of mine was on a Fokker F-50 that sprung a major leak on the left main landing gear. The fluid was literally gushing out as the plane was taxiing out to the runway. The flight crew had no indication in the cockpit.

I used to work on F-4J AWG-10 radar, and saw a radome full of hydraulic fluid that leaked from the antenna.

51 posted on 11/25/2001 12:59:43 AM PST by peabers
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To: Nita Nupress
My experience was with air traffic control rather than design and mechanics.

I donno......

But why in the world would there be a cover-up?

If it is proved to be a terrorist act it will just further inflame Americans and make it easier for the Administration to pursue its goal of killing OBN et al.

52 posted on 11/25/2001 2:46:10 AM PST by JimVT
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To: Traction
My theory is a main tire exploded after stowing (first rumble), causing damage to fuel feed line and pumps within the wheel well. This downed a 727 in Mexico in the 70s which caused the segregation and protection of hydraulics and fuel lines running within the wheel wells. This lesson has been lost on modern aircraft designers which routinely run hydraulics and fuel lines through the wheel wells without any shrapnel protection. The second rumble was the engine starting to miss from lack of fuel and going into a series of compressor surges that loosen something that hit the tail causing lost of rudder control (three violent full swings were recorded).
Truly excellent analysis! But wouldn't a tire exploding be picked up on the CVR? Or, for that matter, if a tire can explode and not be picked up on a cockpit audio recording, could a bomb explode in the luggage and not be picked up? In either case, I think you are correct that it was a loss of controls due to some kind of failure, explosion, incendiary, etc. This is consistent with eyewitness reports of a "flash" and debris coming from the wing-root.

I also think the loss of the vert stab and engines were both due to air load, not a g-load on the engines. That would have sent the engines in opposite directions. They were found near each other. I also doubt there was sufficient energy in the system to create such a g-load. The engines, after all, have to stay on at maximum thrust. But get the cowling sideways, and the mass of the airplane becomes the hammer and the air becomes the anvil.

53 posted on 11/25/2001 3:59:10 AM PST by eno_
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To: JimVT
I cannot explain this inconsistency: The FBI is known to be investigating the otherwise unremarkable disappearance of a Harvard biologist, and they are swabbing down every inch of a 94 year old woman's house, the hair salon she went to, etc. while there is no criminal invetisgation in an airplane crash that happened almost within sight of the WTC ruins when Bush was standing right there, there was a specific threat of more plane disasters, and a probable saboteur had been caught in a shipping container on his way to Canada with fake airline maintenence IDs. Nope, can't be terrorism!

"Coverup" is too strong a word. It implies some kind of criminal intent. I think the downplaying of terrorism in this case is just part of general propoganda and ass-covering. Who would want to admit they could still reach out and touch us that way? Why risk an unpredictable public reaction? So those of us who fly a lot are left to our own to figure out what probably happened.

54 posted on 11/25/2001 4:06:52 AM PST by eno_
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To: BADJOE
I am a private pilot with 3500 hours. I have also discussed this event with my brother who is a retired Delta captain.

This is the most plausible explantion yet for this crash.

You mean to say that the puddle of hydraulic fluid on the ground beneath you aircraft wouldn’t give you pause? Wouldn’t other pilots lining up for take-off be “eyeballing” your equipment?

55 posted on 11/25/2001 4:23:01 AM PST by ivanhoe116
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To: ivanhoe116
A puddle yes. But a tiny hole drilled in a hydraulic line would hardly make a puddle. Even under pressure the stream would be small but steady. And there are plenty of places the fluid could pool within the engine narcell and not be visable from the outside.
56 posted on 11/25/2001 4:45:51 AM PST by BADJOE
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Comment #57 Removed by Moderator

To: eno_
Going back to this problem with the yaw that would have occurred in a climbing turn, by failure of the vertical fin on the rudder. The first response of the airframe based on physics would be to move out at a straight vector from the point where the tail fin became detached, as there was no further force application to continue the turn. Then, in a effort by the pilot to compensate, greater power was applied to the engine on the outside radius of the (formerly) curvilinear path, which is now proceeding out at a tangent. This caused the now rudderless airframe to spin like a boomerang, all the while with increasing engine speed on the outside engine. But now the plane of rotation is turned sharply, on both engines, which are, remember, essentially huge gyroscopes, and in attempting to maintain the motion vectors, twist OFF their pylon mounts and fall away from the plane.

This brings us back to the original question - why did the vertical tail fin mounts, and consequently the rudder mechanism, fail?

58 posted on 11/25/2001 10:01:37 AM PST by alloysteel
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To: peabers
I have flown the Fk-100 and any sort of hydraulic leak like you described would trigger a hydraulic "LO QTY" (low quantity) warning light with repetitive aural chimes. The quantity is sensed inside the reservoir, so the lines would have to bleed off before the reservoir level dropped, but that wouldn't take long at 3000 psi. I'll bet the Fk-50 is similar, and can't explain your friend's experience.
59 posted on 11/25/2001 10:28:13 AM PST by Chad
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To: eno_
Your point is well-taken!
60 posted on 11/25/2001 10:46:09 AM PST by Chad
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